Over the course of just one year, Claire Goodwin’s life turned completely upside down.

Her twin brother moved to Russia, her sister left home on bad terms, her father moved away and became unreachable, she and her partner broke up, and she lost her job.

From October to December 2012, she lost weight rapidly.

“Eating was an unnecessary expense, worry, and inconvenience,” says Goodwin. “My stomach had been in a knot and my heart [had been] in my throat for months.”

“I was so stressed, anxious, and preoccupied that I didn’t feel hunger. Swallowing food made me nauseous, and tasks like cooking or doing dishes seemed overwhelming and insignificant when compared to my bigger problems,” she shares with Healthline.

Though my weight loss has never been nearly as significant as Goodwin’s, I too struggle to maintain my appetite when I’m extremely stressed.

I have generalized anxiety disorder (GAD) and in moments of high stress — like when I was in a one-year accelerated master’s degree program and working part-time — my desire to eat vanishes.

Although many people binge eat or indulge in rich foods when stressed, there’s a small group of people who lose their appetite during moments of high anxiety.

These people, according to Zhaoping Li, MD, director at the UCLA Center for Human Nutrition, are less common than people who respond to stress by binge eating.

But there are still a significant number of people who lose their appetite when they’re anxious. According to the American Psychological Association’s 2015 survey, 39 percent of people said they’ve overeaten or eaten unhealthy foods in the past month due to stress, while 31 percent said they’ve skipped a meal because of stress.

The fight-or-flight response shifts focus to the root of stress

Li says this problem can be traced all the way back to the origins of the fight-or-flight response.

Thousands of years ago, anxiety was the result of a response to an uncomfortable or stressful situation, such as being chased by a tiger. Some people’s response on seeing a tiger would be to run away as fast as they can. Other people might freeze or hide. Some might even charge the tiger.

This same principle applies to why certain people lose their appetite when anxious, while others overeat.

“There are people who respond to any stress with ‘the tiger’s on my tail’ [perspective],” Li says. “I cannot do anything but run. Then there are other people who try to make themselves more relaxed or more in a pleasurable state — that’s actually the majority of people. Those people eat more food.”

People who lose their appetite are so consumed by the source of their stress or anxiety that they can’t do anything else, including necessary tasks like eating.

This feeling is all too real for me. I recently had a deadline looming for weeks on a long article I just couldn’t bring myself to write.

As my deadline approached and my anxiety skyrocketed, I began ferociously typing away. I found myself missing breakfast, then missing lunch, then realizing it was 3 p.m. and I still hadn’t eaten. I wasn’t hungry, but knew I should probably eat something since I often get migraines when my blood sugar is too low.

31 percent of people say they’ve skipped a meal in the last month because of stress.

Physical sensations from stress can suppress appetite

When Mindi Sue Black recently lost her father, she dropped a significant amount of weight. She forced herself to nibble here and there, but had no desire to eat.

“I knew I should eat, but I just couldn’t,” she tells Healthline. “The thought of chewing anything put me in a tailspin. It was a chore to drink water.”

Like Black, some people lose their appetite due to the physical sensations associated with anxiety that make the thought of eating unappetizing.

“Often times, stress manifests itself through physical sensations in the body, such as nausea, tense muscles, or a knot in the stomach,” says Christina Purkiss, a primary therapist at The Renfrew Center of Orlando, an eating disorder treatment facility.

“These sensations could lead to difficulty being in tune with hunger and fullness cues. If someone is feeling intensely nauseous due to stress, it will be challenging to accurately read when the body is experiencing hunger,” Purkiss explains.

Raul Perez-Vazquez, MD, says that some people also lose their appetite due to the increase in cortisol (the stress hormone) that can happen during times of high anxiety.

“In the acute or immediate setting, stress causes increased levels of cortisol, which in turn increases acid production in the stomach,” he says. “This process is meant to help the body quickly digest food in preparation for ‘fight-or-flight,’ which is mediated by adrenaline. This process also, for the same reasons, decreases appetite.”

This increase in stomach acid can also lead to ulcers, something Goodwin experienced from not eating. “I developed a stomach ulcer from the long stretches with only acid in my belly,” she says.

How to regain your appetite if you lose it

Black says she knows she should be eating, and has taken precautions to ensure her health is still a priority. She makes herself eat soup and tries to stay active.

“I make sure to go for a long walk twice a day with my dog to make sure my muscles aren’t atrophying from the weight loss, I do yoga to stay focused, and I play the occasional pick-up soccer game,” she says.

If you’ve lost your appetite due to anxiety or stress, try taking one of these steps to regain it:

1. Identify your stressors

Figuring out the stressors that are causing you to lose your appetite will help you get to the root of the problem. Once you identify these stressors, you can work with a therapist to figure out how to control them.

“Focusing on stress management will, in turn, lead to a decrease in physical symptoms associated with stress,” Purkiss says.

In addition, Purkiss recommends being aware of the physical sensations that can accompany stress, such as nausea. “When you’re able to determine that nausea is likely related to these feelings, it should be a cue that even though it may feel uncomfortable, it is still essential to eat for health,” she says.

2. Make sure you’re getting enough sleep

Li says that getting sufficient restful sleep is crucial for combating lack of appetite due to stress. Otherwise, the cycle of not eating will be more difficult to escape.

3. Consider eating on a schedule

“Someone who has been eating less as a response to a decrease in appetite may need to eat ‘mechanically,’ in order for hunger cues to return,” she says. This can mean setting a timer for meal and snack times.

4. Find foods you can tolerate, and stick to them

When my anxiety is high, I often don’t feel like eating a big, indulgent meal. But I still know I need to eat. I’ll eat mild foods like brown rice with chicken broth, or white rice with a small piece of salmon, because I know my belly needs something in it.

Find something you can stomach during your most stressful periods — maybe a food bland in flavor or one dense in nutrients, so you don’t have to eat as much of it.

Jamie Friedlander is a freelance writer and editor with a passion for health. Her work has appeared in The Cut, Chicago Tribune, Racked, Business Insider, and Success Magazine. When she’s not writing, she can usually be found traveling, drinking copious amounts of green tea, or surfing Etsy. You can see more samples of her work on herwebsite. Follow her onTwitter.